Penetration Capacity Analysis of Distributed Generation Considering Overcurrent Relay Protection and Flux-Coupling Type FCL

In light of the rapid development of the electric power grid, the integrated application of distributed generation (DG) units can be considered as a key driver. Nevertheless, along with large number of DG units are connected into a distribution network, maybe different kinds of effects are accordingly induced. In particular, regarding the configured relay protection, its selectivity and sensitivity may be affected. In this paper, the penetration capacity analysis of DG considering overcurrent relay protection and flux-coupling type FCL is conducted. Under different fault conditions, the theoretical impacts of introducing DG on the fault current are investigated, and a flux-coupling type FCL is suggested to limit the fault current and potentially enhance the DG’s access capacity. Furthermore, the detailed simulation model of a typical distribution network integrated with the DG and FCL is created. From the simulation results, the employment of the FCL can effectively reduce the fault current’s negative influence on the DG, and improve the DG’s access capacity to a certain extent.